System for assisting rescuers in performing cardio-pulmonary resuscitation (CPR) on a patient

Abstract

A system for assisting a rescuer in performing cardio-pulmonary resuscitation (CPR) on a patient includes: a proximity sensor configured to be positioned at a location corresponding to a location of a rescuer's hand when delivering compressions to a patient's chest, the proximity sensor configured to produce a signal indicative of the rescuer's hands being released from the patient's chest; a medical device operatively coupled with the proximity sensor and configured to provide resuscitative treatment to the patient; and a controller communicatively coupled with the medical device and the proximity sensor. The controller is configured to: determine, based upon the signal from the proximity sensor, if the rescuer's hands have been released from the patient's chest, and trigger an action by the medical device in response to a determination that the rescuer's hands have been released from the patient's chest.

The invention claimed is: 
     
       1. A system for assisting a rescuer in performing cardio-pulmonary resuscitation (CPR) on a patient, the system comprising:
 a proximity sensor configured to be positioned at a location corresponding to a location of a rescuer's hand when delivering compressions to a patient's chest, the proximity sensor configured to produce a signal indicative of the rescuer's hands being released from the patient's chest; 
 a medical device operatively coupled with the proximity sensor and configured to provide resuscitative treatment to the patient; and 
 a controller communicatively coupled with the medical device and the proximity sensor, and the controller configured to:
 determine, based upon the signal from the proximity sensor, if the rescuer's hands have been released from the patient's chest, and 
 trigger an action by the medical device in response to a determination that the rescuer's hands have been released from the patient's chest. 
 
 
     
     
       2. The system of  claim 1 , wherein the proximity sensor comprises at least one of a capacitive sensor, an ultrasonic sensor, an E-field sensor, and a light emitter-receiver pair. 
     
     
       3. The system of  claim 2 , wherein the determination that the rescuer's hands have been released from the patient's chest is based on a measurement from the proximity sensor that the rescuer's hands are greater than 1 cm away from the patient's chest. 
     
     
       4. The system of  claim 1 , wherein the medical device is a defibrillator comprising an electrical storage device capable of delivering a therapeutic pulse to a patient. 
     
     
       5. The system of  claim 4 , wherein the action is charging the electrical storage device of the defibrillator. 
     
     
       6. The system of  claim 1 , further comprising at least one sensor operatively connected to the controller for obtaining one or more electrocardiogram (ECG) signals from the patient. 
     
     
       7. The system of  claim 6 , wherein the controller is further configured to:
 determine, based upon the signal from the proximity sensor, if the rescuer's hands are in contact with the patient's chest, 
 analyze the one or more ECG signals from the patient during delivery of chest compressions to the patient, and 
 determine a desirability of a shock to the patient based on the analysis of the one or more ECG signals during the delivery of chest compressions of a CPR cycle. 
 
     
     
       8. The system of  claim 7 , wherein the action is an analysis of one or more ECG signals acquired in an absence of chest compressions to reconfirm the desirability of the shock to the patient, the absence of chest compressions being based on the determination of whether the rescuer's hands have been released from the patient's chest. 
     
     
       9. The system of  claim 6 , wherein the controller is configured to:
 perform at least one transformation of at least a portion of the one or more ECG signals from the patient into frequency domain data based on the determination of whether the rescuer's hands have been released from the patient's chest, 
 determine a first frequency-based value over a first evaluation period based on the at least one transformation, 
 determine a second frequency-based value representing a trend over a second evaluation period based on the at least one transformation, 
 determine a probability of therapeutic success based at least in part on the first frequency-based value and the second frequency-based value, and 
 provide an indication of the probability of therapeutic success. 
 
     
     
       10. The system of  claim 9 , wherein the first frequency-based value comprises an amplitude spectral area (AMSA) value and the second frequency-based value comprises an AMSA trend. 
     
     
       11. The system of  claim 1 , wherein the medical device comprises a feedback device operatively connected to the controller. 
     
     
       12. The system of  claim 11 , wherein the feedback device is configured to provide feedback received from the controller to the rescuer regarding compressions. 
     
     
       13. The system of  claim 11 , wherein the action is providing an indication via the feedback device to provide ventilation to the patient. 
     
     
       14. The system of  claim 13 , wherein the indication is at least one of an audio indication and a visual indication. 
     
     
       15. A method for assisting a rescuer in performing cardio-pulmonary resuscitation (CPR) on a patient, the method comprising:
 positioning a proximity sensor at a location corresponding to a location of a rescuer's hand when delivering compressions to a patient's chest; 
 producing, with the proximity sensor, a signal indicative of the rescuer's hands being released from the patient's chest; 
 determining, by a controller communicatively coupled with a medical device and the proximity sensor, if the rescuer's hands have been released from the patient's chest based upon the signal from the proximity sensor; and 
 triggering, by the controller, an action by the medical device in response to a determination that the rescuer's hands have been released from the patient's chest. 
 
     
     
       16. The method of  claim 15 , further comprising obtaining, by the controller, one or more electrocardiogram (ECG) signals from the patient. 
     
     
       17. The method of  claim 16 , further comprising
 determining, by the controller, if the rescuer's hands are in contact with the patient's chest based upon the signal from the proximity sensor, 
 analyzing, by the controller, the one or more ECG signals from the patient during delivery of chest compressions to the patient; and 
 determining, by the controller, a desirability of a shock to the patient based on the analysis of the one or more ECG signals during the delivery of chest compressions of a CPR cycle. 
 
     
     
       18. The method of  claim 17 , wherein the action is an analysis, by the controller, of one or more ECG signals acquired in an absence of chest compressions to reconfirm the desirability of the shock to the patient, the absence of chest compressions being based on the determination of whether the rescuer's hands have been released from the patient's chest. 
     
     
       19. The method of  claim 16 , wherein the action is:
 performing, by the controller, at least one transformation of at least a portion of the one or more ECG signals from the patient into frequency domain data based on the determination of whether the rescuer's hands have been released from the patient's chest; 
 determining, by the controller, a first frequency-based value over a first evaluation period based on the at least one transformation; 
 determining, by the controller, a second frequency-based value representing a trend over a second evaluation period based on the at least one transformation; 
 determining, by the controller, a probability of therapeutic success based at least in part on the first frequency-based value and the second frequency-based value; and 
 providing, by the controller, an indication of the probability of therapeutic success. 
 
     
     
       20. The method of  claim 19 , wherein the first frequency-based value comprises an amplitude spectral area (AMSA) value and the second frequency-based value comprises an AMSA trend. 
     
     
       21. The method of  claim 15 , wherein the action is providing, by the controller, an indication to ventilate the patient.